Displaying publications 21 - 40 of 278 in total

Abstract:
Sort:
  1. Breeding structure of a colonizing species: Aedes albopictus (Skuse) in peninsular Malaysia and Borneo
    Black WC, Hawley WA, Rai KS, Craig GB
    Heredity (Edinb), 1988 Dec;61 ( Pt 3):439-46.
    PMID: 3230033
    The mosquito, Aedes albopictus, has recently become established in a number of cities throughout the United States. An initial survey of allozyme and genotypic frequencies in U.S. populations (Black et al., 1988) revealed an extensive amount of local differentiation of populations and suggested that much genetic drift may have accompanied colonization. A study of gene flow was initiated in native habitats of Ae. albopictus in Malaysia to determine if the result observed in the U.S. was a consequence of colonization or simply followed the natural breeding structure of the species. Allelic and genotypic frequencies were monitored at ten enzymatic loci in 11 populations from peninsular Malaysia and Borneo. Multiple populations were sampled within the districts of Kuala Lumpur and Kuala Trengganu. Peninsular Malaysian and Borneo populations were strongly genetically differentiated. Allele frequencies were significantly different among and within districts in both regions. Variance in allele frequencies among all collections was partitioned into the variance among regions, districts within regions and collections within districts. Almost all of the variance within regions was attributable to local differentiation suggesting that genetic drift is an important component of the natural breeding structure of this species. This indicates that the large amounts of local differentiation found in U.S. populations was not a consequence of recent colonization.
  2. Reducing the overwintering ability of Aedes albopictus by male release
    Hanson SM, Mutebi JP, Craig GB, Novak RJ
    J Am Mosq Control Assoc, 1993 Mar;9(1):78-83.
    PMID: 8468578
    Eggs of temperate Aedes albopictus populations are cold hardy and can diapause, but tropical populations are not cold hardy and cannot diapause. Heterozygotes possess intermediate diapause and cold hardiness. Males of a tropical strain from Malaysia with a distinctive genetic marker were released into an existing temperate population in East St. Louis, Illinois. Subsequent egg samples from the release site had genetic marker frequency of up to 24%. Reduced cold hardiness and decreased diapause incidence were also observed in the release site population. No such changes occurred at a nearby control site. The rank order of overwintering survival of eggs at the release site was: Aedes triseriatus > temperate Ae. albopictus > hybrid temperate/tropical Ae. albopictus > tropical Ae. albopictus. Eggs collected from the release population the next summer showed total absence of the genetic marker; presumably carriers were removed by the winter.
  3. HLA and nasopharyngeal cancer
    Simons MJ, Chan SH, Day NE, Wee GB, Shanmugaratnam K
    Prog. Clin. Biol. Res., 1977;16:145-8.
    PMID: 905319
  4. Urolithiasis: History, epidemiology, aetiologic factors and management
    Kachkoul R, Touimi GB, El Mouhri G, El Habbani R, Mohim M, Lahrichi A
    Malays J Pathol, 2023 Dec;45(3):333-352.
    PMID: 38155376
    Urolithiasis is defined as a disease diagnosed by the presence of one or more stones in the urinary tract. It is one of the oldest and most widespread diseases known to man, their discovery and characterisation chronology began with the civilisation's history. This pathology has a multifactorial aetiology, very frequent worldwide with geographic and racial variation, their prevalence is increasing in lockstep with socioeconomic development. In fact, this disorder affects between 2 and 20% of the population, with an approximate recurrence rate of 30% to 50% in 5 years. Furthermore, calciumtype stones, which are composed of calcium oxalate (CaOx) alone or a mixture of CaOx and calcium phosphate are the most common, accounting for more than 80% of cases. The medical management of urolithiasis is done by medical treatments and/or by surgical intervention for the stones extraction by the techniques such as extracorporeal shock wave lithotripsy (ESWL), ureteroscopy (URS), percutaneous nephrolithotomy (PCNL) and open surgery. However, various therapies, including thiazide diuretics and alkaline citrate, are used in an attempt to prevent stones recurrence induced by hypercalciuria and hyperoxaluria, but the scientific evidence for their effectiveness is less convincing. On the other hand, endoscopic and ESWL methods have revolutionised the treatment of urinary lithiasis, but these costly methods, can cause acute kidney injury and decreased renal function, in addition, do not prevent the probability of new stone formation. The deepening of our knowledge on all points relating to this disease is a priority for specialists in order to find adequate solutions for this disease. This review provides an overview of urolithiasis, its history, epidemiology, clinical manifestation, diagnosis and treatment methods.
  5. Fulltext Method optimization on the process of Iontophoresis with laser doppler fluximetry in the assessment of microvascular endothelial function
    Belqes Abdullah, A. T., Yvonne, T. G. B., Ahmad, S. H., Abdul Aziz, A. S. I., Aida, H. G. R.
    Malaysian Journal of Medicine and Health Sciences, 2011;7(1):35-40.
    MyJurnal
    Introduction: Iontophoresis of vasoactive substances such as acetylcholine (ACh) and sodium nitroprusside (SNP) combined with Laser Doppler fluximetry (LDF) is a non-invasive tool used to determine microvascular endothelial function. This study aims to test the effect of sodium chloride on
    non-specific vasodilatation when used as a vehicle in the process of iontophoresis. This study also aims to define the number of current pulses needed to get the maximum effect during iontophoresis with ACh and SNP using low current strength. Methods: The experiment was conducted in five healthy females. Baseline skin perfusion was taken before administration of seven current pulses. Current strength of 0.007 mA and current density of 0.01 mA/cm2 were used. Acetylcholine was used to assess endothelial dependent vasodilatation, while SNP was used to assess endothelial independent vasodilatation. The mean skin perfusion (AU) responses to the iontophoresis of ACh at the anodal and SNP at the cathode leads were recorded. Sodium chloride (0.9%) was used as a vehicle to obtain concentration of 1% for both ACh and SNP. Iontophoresis of pure vehicle (NaCl) was conducted on a separate day to observe the effect of vehicle only on the iontophoresis process at both anode and cathode. Results: Iontophoresis of NaCl showed no significant increase in perfusion compared to baseline at both anode and cathode. Significant increases in skin perfusion were observed with SNP and ACh; a plateau of ACh was reached from the 3rd pulse onwards; while the plateau of SNP was reached from the 4th pulse onwards. Conclusion: NaCl could be used as a vehicle for Ach and SNP during iontophoresis as it did not cause non-specific vasodilatation. Using five current pulses are adequate for iontophoresis of ACh and SNP to assess microvascular endothelial function.
  6. Immunogenetic aspects of nasopharyngeal carcinoma: I. Differences in HL-A antigen profiles between patients and control groups
    Simons MJ, Wee GB, Day NE, Morris PJ, Shanmugaratnam K, De-Thé GB
    Int J Cancer, 1974 Jan 15;13(1):122-34.
    PMID: 4131857
  7. Reproducibility of laser Doppler fluximetry and the process of iontophoresis in assessing microvascular endothelial function using low current strength
    Al-Tahami BA, Yvonne-Tee GB, Halim AS, Ismail AA, Rasool AH
    Methods Find Exp Clin Pharmacol, 2010 Apr;32(3):181-5.
    PMID: 20448860 DOI: 10.1358/mf.2010.32.3.1423887
    Iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) combined with laser Doppler fluximetry (LDF) is a tool used to determine microvascular endothelial function. Our aim was to study the reproducibility of different parameters of this technique using iontophoresis with low current strength on the forearm skin of healthy subjects. Baseline skin perfusion was done before application of five current pulses with 1 min of current-free interval. Current strength of 0.007 mA, current density of 0.01 mA/cm(2) and charge density of 6 mC/cm(2) were used, along with 1% ACh and 1% SNP. The absolute maximum change in perfusion (max), percent change in perfusion (% change), peak change in perfusion (peak) and area under the curve during iontophoresis (AUC) at the anodal and cathodal leads were recorded. Measurements were performed in three sessions for 2 days. The coefficient of variation (CV) was calculated for each parameter. Among the parameters studied, maximum change in perfusion and peak flux were the most reproducible parameters.
  8. Fulltext Chromosome 13q deletion with Cornelia de Lange syndrome phenotype
    Ngo CT, Alhady M, Tan AK, Norlasiah IS, Ong GB, Chua CN
    Med J Malaysia, 2007 Mar;62(1):74-5.
    PMID: 17682579
    A 3-year-old girl with facial dysmorphic features suggestive of Cornelia de Lange syndrome was seen in the ophthalmology unit for a right leukocoria. The leukocoria was found to be caused by a large retinoblastoma and the right eye was enucleated. Chromosomal analysis revealed partial chromosome 13q deletion involving band 14 which is associated with a high risk of retinoblastoma. This case shows that patient with chromosome 13q deletion syndrome cannot be diagnosed based on dysmorphic features only. Chromosomal analysis is warranted in all infants with facial dysmorphism suggestive of Cornelia de Lange syndrome so that those with chromosome 13q deletion can be referred early for early detection of retinoblastoma.
  9. Past and future of the EU-habitat directive species Liparis loeselii in relation to landscape and habitat dynamics in SW-Texel, the Netherlands
    Kooijman AM, Bruin CJW, van de Craats A, Grootjans AP, Oostermeijer JGB, Scholten R, et al.
    Sci Total Environ, 2016 Oct 15;568:107-117.
    PMID: 27289393 DOI: 10.1016/j.scitotenv.2016.05.086
    Dune slacks are important habitats, with many endangered plant species. A series of eleven dune slacks of 1-42years old was studied in SW-Texel, the Netherlands, with the EU-habitat directive species Liparis loeselii present in all except the youngest and oldest. Analysis of aerial photographs revealed that new slacks are currently formed every 4-5years. In each slack, topsoil and vegetation data were collected in 2010 and 2014-2015. During succession, vegetation changed from brackish pioneer stages to dune slacks with L. loeselii and Parnassia palustris and ultimately grassland species. Differences between dune slacks and sampling periods were mostly significant. Herb cover and soil C increased with slack age, and over the five year study period, while bare sand, bulk density and pH decreased. The annual pH-decrease was 0.055 and 0.075 for pH-H2O and pH-KCl respectively, and annual C-increase 0.16% and 35gm(-2). Liparis loeselii was only present between pHH2O 5.8-7.5 and pHKCl 5.6-7.6, and only occurred at C-content below 4.3%. In lime-poor dunes, environmental conditions thus become unsuitable approximately 34years after the start of succession. In the dune slacks, Liparis loeselii established within 6years, showed peak values after 11-16years, and declined until conditions became unsuitable. Rejuvenation may occur after large storms with fresh sand deposits. However, even with further succession, the present populations are not endangered and probably last until 2040. With new dune slacks every 5years, L. loeselii occurs in approximately eight different dune slacks at the same time, ensuring viable populations also in the future. This shows that adverse effects of succession can be counteracted by dynamics on local and landscape scale.
  10. Fulltext Infodemiological patterns in searching medication errors: relationship with risk management and shift work
    Di Simone E, Di Muzio M, Dionisi S, Giannetta N, Di Muzio F, De Gennaro L, et al.
    Eur Rev Med Pharmacol Sci, 2019 Jun;23(12):5522-5529.
    PMID: 31298407 DOI: 10.26355/eurrev_201906_18224
    INTRODUCTION: Western world health care systems have been trying to improve their efficiency and effectiveness in order to respond properly to population aging and non-communicable diseases epidemic. Treatment of the elderly population is becoming complex due to the high number of prescribed drugs because of multimorbidity. Errors in drugs administration in different health care related settings are an actual important issue due to different causes. Aim of this observational study is to measure the online interest in seeking medication errors information related to risk management and shift work.

    MATERIALS AND METHODS: We investigated Google Trends® for popular search relating to medication errors, risk management and shift work. Relative search volumes (RSVs) were evaluated from 2008 to 2018. A comparison between RSV curves related to medication errors, risk management and shift work was carried out. Then, we compared the world to Italian search.

    RESULTS: RSVs were persistently higher for risk management than for medication errors (mean RSVs 069 vs. 48%) and RSVs were stably higher for medication errors than shift work (mean RSVs 48 vs. 22%). In Italy, RSVs were much lower compared to the rest of the world, and RSVs for medication errors during the study period were negligible. Mean RSVs for risk management and shift work were 3 and 25%, respectively. RSVs related to medication errors and clinical risk management were correlated (r=0.520, p<0.0001).

    CONCLUSIONS: Google Trends® search query volumes related to medication errors, risk management and shift work are different. RSVs for risk management are higher, and they are correlated with medication errors. Also, shift work search appears to be lower. These results should be interpreted in order to correctly evaluate how to decrease the number of medication errors in different health care related setting.

  11. Fulltext Heat acclimation attenuates the increased sensations of fatigue reported during acute exercise-heat stress
    Willmott AGB, Hayes M, James CA, Gibson OR, Maxwell NS
    Temperature (Austin), 2019 Sep 19;7(2):178-190.
    PMID: 33015245 DOI: 10.1080/23328940.2019.1664370
    Athletes exercising in heat stress experience increased perceived fatigue acutely, however it is unknown whether heat acclimation (HA) reduces the magnitude of this perceptual response and whether different HA protocols influence the response. This study investigated sensations of fatigue following; acute exercise-heat stress; short- (5-sessions) and medium-term (10-sessions) HA; and between once- (ODHA) and twice-daily HA (TDHA) protocols. Twenty male participants (peak oxygen uptake: 3.75 ± 0.47 L·min-1) completed 10 sessions (60-min cycling at ~2 W·kg-1, 45°C/20% relative humidity) of ODHA (n = 10) or non-consecutive TDHA (n = 10). Sensations of fatigue (General, Physical, Emotional, Mental, Vigor and Total Fatigue) were assessed using the multi-dimensional fatigue scale inventory-short form pre and post session 1, 5 and 10. Heat adaptation was induced following ODHA and TDHA, with reductions in resting rectal temperature and heart rate, and increased plasma volume and sweat rate (P 
  12. A comparison of two global positioning system devices for team-sport running protocols
    Willmott AGB, James CA, Bliss A, Leftwich RA, Maxwell NS
    J Biomech, 2019 01 23;83:324-328.
    PMID: 30563764 DOI: 10.1016/j.jbiomech.2018.11.044
    The comparability and reliability of global positioning system (GPS) devices during running protocols associated with team-sports was investigated. Fourteen moderately-trained males completed 690 m of straight-line movements, a 570 m change of direction (COD) course and a 642.5 m team-sport simulated circuit (TSSC); on two occasions. Participants wore a FieldWiz GPS device and a Catapult MinimaxX S4 10-Hz GPS device. Typical error of measurement (TE) and coefficient of variation (CV%) were calculated between GPS devices, for the variables of total distance and peak speed. Reliability comparisons were made within FieldWiz GPS devices, between sessions. Small TE were observed between FieldWiz and Catapult GPS devices for total distance and peak speed during straight-line (16.9 m [2%], 1.2 km·h-1 [4%]), COD (31.8 m [6%], 0.4 km·h-1 [2%]) and TSSC protocols (12.9 m [2%], 0.5 km·h-1 [2%]), respectively, with no significant mean bias (p > 0.05). Small TE were also observed for the FieldWiz GPS device between sessions (p > 0.05) for straight-line (9.6 m [1%], 0.2 km·h-1 [1%]), COD (12.8 m [2%], 0.2 km·h-1 [1%]) and TSSC protocols (6.9 m [1%], 0.6 km·h-1 [2%]), respectively. Data from the FieldWiz GPS device appears comparable to established devices and reliable across a range of movement patterns associated with team-sports.
  13. Fulltext Heat alleviation strategies for athletic performance: A review and practitioner guidelines
    Gibson OR, James CA, Mee JA, Willmott AGB, Turner G, Hayes M, et al.
    Temperature (Austin), 2020;7(1):3-36.
    PMID: 32166103 DOI: 10.1080/23328940.2019.1666624
    International competition inevitably presents logistical challenges for athletes. Events such as the Tokyo 2020 Olympic Games require further consideration given historical climate data suggest athletes will experience significant heat stress. Given the expected climate, athletes face major challenges to health and performance. With this in mind, heat alleviation strategies should be a fundamental consideration. This review provides a focused perspective of the relevant literature describing how practitioners can structure male and female athlete preparations for performance in hot, humid conditions. Whilst scientific literature commonly describes experimental work, with a primary focus on maximizing magnitudes of adaptive responses, this may sacrifice ecological validity, particularly for athletes whom must balance logistical considerations aligned with integrating environmental preparation around training, tapering and travel plans. Additionally, opportunities for sophisticated interventions may not be possible in the constrained environment of the athlete village or event arenas. This review therefore takes knowledge gained from robust experimental work, interprets it and provides direction on how practitioners/coaches can optimize their athletes' heat alleviation strategies. This review identifies two distinct heat alleviation themes that should be considered to form an individualized strategy for the athlete to enhance thermoregulatory/performance physiology. First, chronic heat alleviation techniques are outlined, these describe interventions such as heat acclimation, which are implemented pre, during and post-training to prepare for the increased heat stress. Second, acute heat alleviation techniques that are implemented immediately prior to, and sometimes during the event are discussed. Abbreviations: CWI: Cold water immersion; HA: Heat acclimation; HR: Heart rate; HSP: Heat shock protein; HWI: Hot water immersion; LTHA: Long-term heat acclimation; MTHA: Medium-term heat acclimation; ODHA: Once-daily heat acclimation; RH: Relative humidity; RPE: Rating of perceived exertion; STHA: Short-term heat acclimation; TCORE: Core temperature; TDHA: Twice-daily heat acclimation; TS: Thermal sensation; TSKIN: Skin temperature; V̇O2max: Maximal oxygen uptake; WGBT: Wet bulb globe temperature.
  14. Newborn Screening TSH Values Less Than 15 mIU/L Are Not Associated With Long-term Hypothyroidism or Cognitive Impairment
    West R, Hong J, Derraik JGB, Webster D, Heather NL, Hofman PL
    J Clin Endocrinol Metab, 2020 09 01;105(9).
    PMID: 32598474 DOI: 10.1210/clinem/dgaa415
    BACKGROUND: It is unclear whether newborns with mild thyrotropin elevation (mTSHe) are at risk of neurocognitive impairment. We assessed whether mTSHe at birth persists during childhood and compared neurocognitive functioning to siblings.

    METHODS: This study encompassed children born in the Auckland region (New Zealand) with a newborn screen TSH level of 8 to 14 mIU/L blood, age 6.9 to 12.6 years at assessment, and their siblings. Thyroid function tests (serum TSH and free thyroxine) and neurocognitive assessments were performed, including IQ via the Wechsler Intelligence Scale for Children, fourth edition.

    RESULTS: Ninety-six mTSHe individuals were studied, including 67 children recruited with 75 sibling controls. Mean mTSHe newborn TSH level was 10.1 mIU/L blood and 2.4 mIU/L at assessment (range, 0.8-7.0 mIU/L, serum). Although higher newborn TSH levels in the mTSHe group correlated with lower full-scale IQ scores (r = 0.25; P = .040), they were not associated with the magnitude of the IQ difference within sibling pairs (P = .56). Cognitive scores were similar for mTSHe and controls (full-scale IQ 107 vs 109; P = .36), with a minor isolated difference in motor coordination scores.

    CONCLUSIONS: Our data do not suggest long-term negative effects of neonatal mild TSH elevation. TSH elevation below the screen threshold appears largely transient, and midchildhood neurocognitive performance of these children was similar to their siblings. We propose that associations between neonatal mild TSH elevation and IQ are due to familial confounders. We caution against the practice of reducing screening CH cutoffs to levels at which the diagnosis may not offer long-term benefit for those detected.

  15. Chlorogenic acid attenuates kidney fibrosis via antifibrotic action of BMP-7 and HGF
    Yunus J, Salman M, Lintin GBR, Muchtar M, Sari DCR, Arfian N, et al.
    Med J Malaysia, 2020 05;75(Suppl 1):5-9.
    PMID: 32471962
    BACKGROUND: Kidney fibrosis, characterised by tubulointerstitial fibrosis, is a histological landmark of chronic kidney disease. The body attempts to compensate for progressive detrimental process of kidney fibrosis by producing antifibrotic substances, such as bone morphogenetic protein-7 (BMP-7) and hepatocyte growth factor (HGF). Chlorogenic acid is known to have renoprotective and antifibrotic properties. This study aims to evaluate the effect of chlorogenic acid on unilateral ureteral obstruction (UUO)-induced kidney fibrosis mice model.

    METHODS: This study was a quasi-experimental with posttestonly control group design. Twenty-five adult male Swiss Webster mice were randomly divided into five groups: shamoperated group (SO), UUO-control day-7 (U7), UUO-control day-14 (U14), UUO-chlorogenic acid day-7 (UC7), and UUOchlorogenic acid day 14 (UC14). Myofibroblasts were identified by immunohistochemical staining of alphasmooth muscle actin (α-SMA) while collagen fibers were identified by Sirius Red staining. Both data were presented as area fraction. BMP-7 and HGF mRNA expressions were assessed by reverse transcription PCR (RT-PCR). Data were quantified using ImageJ software.

    RESULTS: UUO-control groups (U7 and U14) showed higher α- SMA-immunopositive (6.52±1.33, 18.24±1.39 vs. 0.22±0.01; p<0.05) and Sirius Red-positive area fractions (6.61±0.8, 12.98±2.31 vs. 0.62±0.10; p<0.05), lower BMP-7 (1.02±0.47, 1.18±0.65 vs. 2.09±0.87; p<0.05) and HGF mRNA expressions (1.06±0.31, 0.89±0.14 vs. 1.88±0.81; p<0.05) compared to SO group. UUO-chlorogenic acid groups (UC7 and UC14) showed lower α-SMA-immunopositive (1.24±0.37, 4.58±0.61; p<0.05) and Sirius Red-positive area fractions (4.76±1.03, 3.72±0.54; p<0.05), higher BMP-7 (1.84±0.49, 2.19±0.43; p<0.05) and HGF (1.58±0.38; p>0.05, 1.84±0.42; p<0.05) mRNA expressions compared to UUO-control groups. UUOchlorogenic acid groups showed BMP-7 and HGF mRNA expressions that were not significantly different from the SO group.

    CONCLUSION: Chlorogenic acid administration prevents kidney fibrosis in UUO mice model through modulating antifibrotic pathway.

  16. Fulltext Volume and Intensity of Locomotor Activity in International Men's Field Hockey Matches Over a 2-Year Period
    James CA, Gibson OR, Dhawan A, Stewart CM, Willmott AGB
    Front Sports Act Living, 2021;3:653364.
    PMID: 34127962 DOI: 10.3389/fspor.2021.653364
    The locomotor demands of international men's field hockey matches were investigated across positions (DEF, MID, FWD) and playing quarters. Volume (i.e., total values) and intensity (i.e., relative to playing time) data were collected using 10-Hz GPS/100-Hz accelerometer units from the #11 world-ranked (WR) team, during 71 matches, against 24 opponents [WR 12 ± 11 (range, 1-60)]. Mean ± SD team total distance (TD) was 4,861 ± 871 m, with 25% (1,193 ± 329 m) "high-speed running" (>14.5 km h-1) and 8% (402 ± 144 m) "sprinting" (>19.0 km h-1). Reduced TD (range, -3 to 4%) and average speed (range, -3.4 to 4.7%) occurred through subsequent quarters, vs. Q1 (p < 0.05). A "large" negative relationship (r = -0.64) was found between playing duration and average speed. Positional differences (p < 0.05) were identified for all volume metrics including; playing duration (DEF, 45:50 ± 8:00 min; MID, 37:37 ± 7:12 min; FWD, 33:32 ± 6:22 min), TD (DEF, 5,223 ± 851 m; MID, 4,945 ± 827 m; FWD, 4,453 ± 741 m), sprinting distance (DEF, 315 ± 121 m; MID, 437 ± 144 m; FWD, 445 ± 129 m), and acceleration efforts (>2 m s-2; DEF, 48 ± 12; MID, 51 ± 11; FWD, 50 ± 14). Intensity variables similarly revealed positional differences (p < 0.05) but with a different pattern between positions; average speed (DEF, 115 ± 10 m min-1; MID, 132 ± 10 m min-1; FWD, 134 ± 15 m min-1), sprinting (DEF, 7 ± 3 m min-1; MID, 12 ± 4 m min-1; FWD, 14 ± 4 m min-1), and accelerations (DEF, 1.1 ± 0.3 n min-1; MID, 1.4 ± 0.2 n min-1; FWD, 1.5 ± 0.3 n min-1). Physical outputs reduced across playing quarters, despite unlimited substitutions, demonstrating the importance of optimizing physical preparation prior to international competition. Volume and intensity data highlight specific positional requirements, with forwards displaying shorter playing durations but greater high-intensity activities than defenders.
  17. Morphological alterations of Thymus during the early murine leishmaniasis
    Arrais-Lima C, Lima LR, Faria MGBF, Degrossoli A, Arrais-Silva WW, Souto PCS
    Trop Biomed, 2021 Sep 01;38(3):338-342.
    PMID: 34508341 DOI: 10.47665/tb.38.3.075
    Leishmaniasis is a neglected and endemic disease that affects poorest population mainly in developing countries. Thymus provides an essential complex environment for T cell maturation and differentiation during leishmania infection. The aim of this study was to investigate the pathological alterations of the Thymus during early Leishmania amazonensis murine infection. BALB/c mice were infected with 105 amastigotes for 24 h, 3 days, 7 days, 15 days or 30 days. At different times of infection, the relative weight of the Thymus was obtained, and the Thymus cellularity was determined by counting total cells of one thymic lobe. The thymic lobe was, alternatively, processed for standard Haematoxylin and Eosin protocol. Our results suggest thymic alteration during the early days of BALB/c mice infection with L. amazonensis. The thymic hypertrophy was accompanied by histological alterations in Thymus architecture with thickening cortex at 3 days p.i. and loss of an evident delimitation between the cortex and medulla at 7 days p.i. when compared to the control mice. That is the first time that Thymus hypertrophy was observed during the early leishmaniasis. However, how it may contribute to infection susceptibility requires further investigation.
  18. Short-Term Heat Acclimation and Precooling, Independently and Combined, Improve 5-km Time Trial Performance in the Heat
    James CA, Richardson AJ, Watt PW, Willmott AGB, Gibson OR, Maxwell NS
    J Strength Cond Res, 2018 May;32(5):1366-1375.
    PMID: 28486332 DOI: 10.1519/JSC.0000000000001979
    James, CA, Richardson, AJ, Watt, PW, Willmott, AGB, Gibson, OR, and Maxwell, NS. Short-term heat acclimation and precooling, independently and combined, improve 5-km time trial performance in the heat. J Strength Cond Res 32(5): 1366-1375, 2018-Following heat acclimation (HA), endurance running performance remains impaired in hot vs. temperate conditions. Combining HA with precooling (PC) demonstrates no additive benefit in intermittent sprint, or continuous cycling exercise protocols, during which heat strain may be less severe compared to endurance running. This study investigated the effect of short-term HA (STHA) combined with mixed methods PC, on endurance running performance and directly compared PC and HA. Nine amateur trained runners completed 5-km treadmill time trials (TTs) in the heat (32° C, 60% relative humidity) under 4 conditions; no intervention (CON), PC, short-term HA (5 days-HA) and STHA with PC (HA + PC). Mean (±SD) performance times were; CON 1,476 (173) seconds, PC 1,421 (146) seconds, HA 1,378 (116) seconds and HA + PC 1,373 (121) seconds. This equated to the following improvements versus CON; PC -3.7%, HA -6.6% and HA + PC -7.0%. Statistical differences were only observed between HA and CON (p = 0.004, d = 0.68, 95% CI [-0.27 to 1.63]) however, similar effect sizes were observed for HA + PC vs. CON (d = 0.70, 95% CI [-0.25 to 1.65]), with smaller effects between PC vs. CON (d = 0.34, 95% CI [-0.59 to 1.27]), HA vs. PC (d = 0.33, 95% CI [-0.60 to 1.26]) and HA + PC vs. PC (d = 0.36, 95% CI [-0.57 to 1.29]). Pilot testing revealed a TT typical error of 16 seconds (1.2%). Precooling offered no further benefit to performance in the acclimated individual, despite modest alleviation of physiological strain. Maintenance of running speed in HA + PC, despite reduced physiological strain, may indicate an inappropriate pacing strategy therefore, further familiarization is recommended to optimize a combined strategy. Finally, these data indicate HA, achieved through cycle training, yields a larger ergogenic effect than PC on 5-km running performance in the heat, although PC remains beneficial when HA is not possible.
  19. HLA antigens in three common populations in South East Asia--Chinese, Malay and Filipino
    Chan SH, Wee GB, Srinivasan N, Glen SP, Cheng P, Vengadasalam D, et al.
    Tissue Antigens, 1979 May;13(5):361-8.
    PMID: 91213
  20. Short-term heat acclimation improves the determinants of endurance performance and 5-km running performance in the heat
    James CA, Richardson AJ, Watt PW, Willmott AG, Gibson OR, Maxwell NS
    Appl Physiol Nutr Metab, 2016 Nov 18.
    PMID: 28177747 DOI: 10.1139/apnm-2016-0349
    This study investigated the effect of 5 days of controlled short-term heat acclimation (STHA) on the determinants of endurance performance and 5-km performance in runners, relative to the impairment afforded by moderate heat stress. A control group (CON), matched for total work and power output (2.7 W·kg(-1)), differentiated thermal and exercise contributions of STHA on exercise performance. Seventeen participants (10 STHA, 7 CON) completed graded exercise tests (GXTs) in cool (13 °C, 50% relative humidity (RH), pre-training) and hot conditions (32 °C, 60% RH, pre- and post-training), as well as 5-km time trials (TTs) in the heat, pre- and post-training. STHA reduced resting (p = 0.01) and exercising (p = 0.04) core temperature alongside a smaller change in thermal sensation (p = 0.04). Both groups improved the lactate threshold (LT, p = 0.021), lactate turnpoint (LTP, p = 0.005) and velocity at maximal oxygen consumption (vV̇O2max; p = 0.031) similarly. Statistical differences between training methods were observed in TT performance (STHA, -6.2(5.5)%; CON, -0.6(1.7)%, p = 0.029) and total running time during the GXT (STHA, +20.8(12.7)%; CON, +9.8(1.2)%, p = 0.006). There were large mean differences in change in maximal oxygen consumption between STHA +4.0(2.2) mL·kg(-1)·min(-1) (7.3(4.0)%) and CON +1.9(3.7) mL·kg(-1)·min(-1) (3.8(7.2)%). Running economy (RE) deteriorated following both training programmes (p = 0.008). Similarly, RE was impaired in the cool GXT, relative to the hot GXT (p = 0.004). STHA improved endurance running performance in comparison with work-matched normothermic training, despite equality of adaptation for typical determinants of performance (LT, LTP, vV̇O2max). Accordingly, these data highlight the ergogenic effect of STHA, potentially via greater improvements in maximal oxygen consumption and specific thermoregulatory and associated thermal perception adaptations absent in normothermic training.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links